A method of bonding an organic modifying group to an inorganic oxide material such as silica gel or zeolite to form an organic inorganic composite material, thus changing chemical and physical properties of the inorganic oxide material, has conventionally be conducted.
The organic inorganic composite material thus obtained has been used in, for example, industrial materials such as various adsorbents, columns and surfactants; pharmaceutical materials such as drug delivery system, biological affinity materials and test chips; and electronic materials such as sensors, organic EL and liquid crystals.
It is generally desired in the organic inorganic composite material that a bond between an organic material (organic group) and an inorganic oxide material (carrier) is strong. In particular, in the case that an organic inorganic composite material is used as a catalyst material, there is the advantage that a strong bond between an organic group constituting an organic inorganic composite material and a carrier suppresses elution (leaching) of catalyst active species, and maintains high-state catalyst activity.
Hitherto, an organic inorganic composite material comprising an organic material and an inorganic oxide material, fixed with a covalent bond at only one place has been known as an organic inorganic composite material used as a catalyst material (Patent Document 1). However, such a covalent bond at only one place was not sufficient for fixation.
It is well known that a catalyst material is used in various chemical reactions. For example, a coupling reaction such as Suzuki-Miyaura coupling reaction using a catalyst, a hydrogenation reaction and the like are very important reactions in synthesis of pharmaceutical and agricultural products and electronic materials. A homogeneous catalyst such as palladium or rhodium has been used as a catalyst in those reactions (Non-Patent Documents 1 and 2).
However, such a homogeneous catalyst has high activity and selectivity, but is difficult to be separated from a product after reaction. This led to the decrease in performance of a product and high cost due to such catalyst being unable to be recycled.
To solve those problems, in recent years heterogeneous catalysts comprising a homogeneous catalyst fixed to various resins have been studied (Patent Document 2). In addition to those technologies, investigations have been made in which an organic group is fixed to silica and other oxides, and an active metal is further coordinated thereto, thereby forming a catalyst (Patent Document 3).
However, in the case that a resin is used as a carrier, there was the problem in durability that a catalyst is deactivated by swelling or the like of a resin, depending on the kind of an organic solvent and a reaction temperature. Furthermore, in the case that an oxide is used as a carrier, a bond between the oxide and an organic group is not strong, leading to the problem that a catalyst component elutes in a reaction liquid. Thus, there was a problem of the decrease in performance of an objective product due to the problem.    Patent Document 1: JP-A 2004-175793    Patent Document 2: JP-A 2005-60335    Patent Document 3: JP-A 2005-255581    Non-Patent Document 1: Tetrahedron Letter, 36, 3437 (1979)    Non-Patent Document 2: Tetrahedron, 40, 1245 (1984)